112 HYDROPHILIDA. 
NITIDULODES. 
Corpus subdepressum. Labrum haud occultum. Mentum bilobum. Coxe anteriores haud omnino contigue. 
Prosternum carinatum. Mesosternum in medio tabula magna anterius acuminata, posterius cum meta- 
sterno sutura recta arcte conjunctum. Characteres ceteri fere ut in genere Pelosomate. 
This insect with many of the characters of Pelosoma combines some others peculiar 
to itself. The labrum is exposed and is very transverse, but not corneous; and the 
mandibles may be seen on either side of it as slender, curved hooks. The mentum 
has in the middle a deep excision reaching halfway to the base and so rendering it 
bilobed. The prosternum is very strongly carinate along the middle; and the termina- 
tion of this carina behind does not appear acuminate (as it does in Pelosoma and 
Cercyon, in both of which, however, it is really minutely notched at the apex), but, 
wing to a slight separation of the coxe, exposes a notch the face of which is directed 
obliquely forwards. The largely developed central piece of the mesosternum is similar 
to that of Pelosoma except for its greater size. 
1. Nitidulodes jansoni. (Tab. III. fig. 15.) 
Ovalis, latiusculus, subdepressus, supra nitidus, rufus, elytris nigris, capite thoraceque lete rufis; antennarum 
basi palpisque testaceis, subtus opacum ; femoribus, metasterni mesosternique mediis nitidis; capite pro- 
thoraceque crebre punctatis; elytris leviter striatis, striis internis versus apicem profundioribus, inter- 
stitiis sat crebre et sat fortiter punctatis. 
Long. 2, lat. 12 lin. 
Hab. Nicaracua, Chontales (Janson). 
Club of antenne very broad and flat; front tibie broad, rounded externally and 
strongly spinulose. Upper surface very shining; the strie of the elytra fine and but 
little impressed, the three or four next the suture, however, are a good deal deepened 
at the extremity; the punctuation of the striz is rather indistinct, but renders them 
nearly crenate; the punctuation of the interstices is rather more distinct at the sides 
and apex than it is near the suture. ‘The middle tibiz are broad and short, the 
hind ones rather more elongate. 
Two individuals of this species have been in my collection for many years; and the 
two in Mr. Godman’s appear to have been taken at the same time as my own; so 
that Mr. Janson presumably only once found the species, which probably has a different 
mode of life from its allies. 
OOSTERNUM. 
Corpus supra tenuiter pubescens, subtus nudum, opacum. Llytra profunde sculpturata. Mentum anterius 
profundeimpressum. Palpi maxillares tenues, parum elongati. Prosternum in medio elevatum, carinatum ; 
pronotum haud inflexum. Mesosternum in medio tabulam ovalem formans. Tibia splnulose. Tarsi 
parvi, quinquearticulati, posteriores articulo primo quam secundus paulo longiore. 
The minute insect separated under this name is closely allied to Cercyon, but differs 
from that genus by numerous details, nearly all of which are points of approach to 
